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Geochemistry of the Laramide igneous suite of theSanta Rita and Empire Mountains, southeastern Arizona
In Partial Fulfillment of the Requirements For the Degree of
MASTER OF SCIENCE
In the Graduate College
THE UNIVERSITY OF ARIZONA
1 9 8 7
STATEMENT BY AUTHOR
This thesis has been submitted in partial fulfillment of requirements for an advanced degree at The University of Arizona and is deposited in the University Library to be made available to borrowers under rules of the Library.
Brief quotations from this thesis are allowable without special permission, provided that accurate acknowledgement of source is made. Requests for permission for extended quotation from or reproduction of this manuscript in whole or in part may be granted by the head of the major department or the Dean of the Graduate College when in his or her judgement the proposed use of the material is in the interests of scholarship. In all other instances, however, permission must be obtained from the author.
Signed:
APPROVAL BY THESIS DIRECTOR
This thesis has been approved on the date shown below:
■ wicfstfienS. R. TITLE?
Professor of Gec^tfiences
A. MDate
ACKNOWLEDGEMENTS
I would like to thank Dr. Spencer R. Titley of the University of Arizona for his support and guidance which began before I enrolled at the University of Arizona and continued throughout the process which has culminated in this thesis. I would further like to thank Dr. Elizabeth Youngblood Anthony who guided me through the intricacies of Instrumental Neutron Activation Analysis. Finally, I would like to thank my wife, Alyce, for her support and patience during my studies.
iii
TABLE OF CONTENTS
Page
LIST OF ILLUSTRATIONS.......... : .......................... vi
LIST OF TABLES .............................................viii
ABSTRACT ............................ ...................... ix
Scope of the Study....................................... 1Physiography and Geology of the Santa Rita/Empire
Mountains ........................................... 4Rationale for Method of S t u d y .......................... 9
2. DESCRIPTION OF THE UNITS ...................... ............ 12
Salero Formation ( S F ) ................................... 12Lower member (SFN) ................................ 13Welded-tuff member (SFS) .......................... 14
Geochemical Evaluation of Weathering and Alteration . . . 23
4. DESCRIPTION OF ANALYTICAL R E S U L T S .............. 26
Major Elements ......................................... 26Mg, P, Ca, Ti, Mn, and F e .......................... 26A1 ................................................. 32Na and K ........................................... 32Ratios of Major Elements .......................... 32
Minor Elements . ......................... 36Sc, Co, Ni, Sr, Zr, and Hf ........................ 36Zn, As, Sb, and Cs ................................. 40Rb, Ba, and Ta ..................................... 40R E E .............................. 43U and Th .................................. 44
iv
V
TABLE OF CONTENTS--Continued
Ratios of K, Rb, Sr, and B a ............................ 44K/Rb ............................................... 48K/Ba ............................................... 48Rb/Sr . . . "......................................... 49S r / B a ...................... ........................ 49
5. DISCUSSION OF ANALYTICAL RESULTS .......................... 54
Major Elements ......................................... 54Mg, P, Ca, Ti, Mn, and F e .......................... 54Al ................................................. 55Na and K ........ .................... .............. 55Ratios of Major Elements .......................... 55
Minor Elements ......................................... 56Sc, Co, Ni, Sr, Zr, and Hf ......................... 56
Ratios of K, Rb, Sr, and B a ............................ 57K/Rb ........................ ...................... 57K/Ba ............................................... 57R b / S r ............................................... 58S r / B a ........................ ...................... 58General Comments ................................... 58
6. GENETIC RELATIONS BETWEEN UNITS ............................ 61
Ti and Z r ...................................... .. . . . 62K/Rb Ratios and Related Values.......................... 67Rare Earth E l e m e n t s ..................................... 68U and Th ............................................... 75Comparisons of Sierrita Samples to Santa Rita and
APPENDIX 1: ANALYTICAL R E S U L T S ............................. 82
APPENDIX 2: LOCATIONS AND CORRELATIONS................ .. . 87
APPENDIX 3: MAJOR ELEMENT VALUES AND RATIOS, PETROLOGICINDICES, AND BARTH KATANORMS .................. 94
APPENDIX 4: ERRORS AND REPRODUCIBILITY .................... 113
Page
LIST OF REFERENCES 116
LIST OF ILLUSTRATIONS
1. Santa Rita and Empire Mountains and Sierrita Mountains,southeastern Arizona ................................. 5
2. Outcrop map of the study area with sample locations . . . . 7
3. MgO vs Si02". Santa Rita and Empire Mountains.............. 27
4. Ti vs SiOg: Santa Rita and Empire Mountains.............. 27
5. FegOgCt) vs SiOg: Santa Rita and Empire Mountains ........ 28
6. CaO vs D. I.: Santa Rita and Empire Mountains............ 29
7. CaO vs SiOg: Santa Rita and Empire Mountains ............ 298. Fe20g(t) vs Ti: Santa Rita and Empire M o untains.......... 31
9. Fe20g(t) vs Ti: Sierrita Mountains . ....................... 31
10. AI2O3 vs Si02: Santa Rita and Empire Mountains ............ 33
11. K2O vs Si02: Santa Rita and Empire Mountains.............. 34
12. Na20 vs Si02: Santa Rita and Empire Mountains............ 34
13. A/CNK(m) vs Si02: Santa Rita and Empire Mountains . . . . . 35
14. Na20/K20 vs Si02: Santa Rita and Empire Mountains ........ 35
15. Co vs S102: Santa Rita and Empire Mountains............... 37
16. Ni vs SiG^: Santa Rita and Empire Mountains............... 37
17. Sr vs Si02: Santa Rita and Empire Mountains............... 38
18. Zr vs Si02: Santa Rita and Empire Mountains............... 38
19. Ti vs Zr: Santa Rita and Empire Mountains................ 39
20. Sr vs CaO: Santa Rita and Empire Mountains................ 39
Figure Page
vi
LIST OF ILLUSTRATIONS--Continued
Figure Fage
21. Rb vs SiOg: Santa Rita and Empire Mountains.............. 41
22. Ba vs SlOg: Santa Rita and Empire Mountains.............. 42
23. Ta vs SiOg: Santa Rita and Empire Mountains.............. 42
24a. REE - JCD and SFS: Santa Rita and Empire Mountains . . . . 45
24b. REE - EHQM: Santa Rita and Empire Mountains....... 45
25a. REE - SFN and KLQ: Santa Rita and Empire Mountains . . . . 46
25b. REE - TKP and GV: Santa Rita and Empire Mountains . . . . 46
26. U vs SiOg: Santa Rita and Empire Mountains................ 4727. Th vs SiOg: Santa Rita and Empire Mountains.............. 47
28. K/Rb vs SiOg: Santa Rita and Empire Mountains............ 50
29. K/Rb vs SiOg: Sierrita Mountains.......................... 50
30. K/Ba vs SiOg: Santa Rita and Empire Mountains............ 51
31. K/Ba vs S102: Sierrita Mountains.......................... 51
32. Rb/Sr vs SiOg: Santa Rita and Empire Mountains ............ 52
33. Rb/Sr vs SiOg: Sierrita Mountains ........................ 52
34. Sr/Ba vs SiOg: Santa Rita and Empire Mountains ............ 53
35. Y/Sr vs SiOg: Santa Rita and Empire M o u ntains............ 60
36. Sr/Zr vs SiOg: Santa Rita and Empire Mountains............ 60
37. Ti vs Zr: Sierrita Mountains............................... 65
38. P2O5 vs total REE: Santa Rita and Empire Mountains . . . . 71
39. Zr vs total REE: Santa Rita and Empire Mountains.......... 71
40. Ti vs total REE: Santa Rita and Empire Mountains.......... 72
vii
LIST OF TABLES
1. Sampled Units with Ages and Correlations by Drewes (1981) . 3
2. Chemical Index of Alteration (C.I.A.) for Samples ........ 25
3. Ce/Yb Values and A v e r a g e s ............................ .. . 70
Table Page
viii
ABSTRACT
Laramide igneous activity in the Santa Rita and Empire
Mountains of southeastern Arizona began prior to 74 Ma and continued
until approximately 55 Ma. Eighteen samples from the Salero Formation,
Corona and Empire stocks, Josephine Canyon Diorite, Elephant Head
Quartz Monzonite, and Late Cretaceous and Paleocene stocks and dikes
were examined by Instrumental Neutron Activation Analysis to provide
reliable trace element concentrations. Ti-Zr, REE, U and Th, and K/Rb
data indicate that the Josephine Canyon Diorite and Elephant Head
Quartz Monzonite are probably genetically related, that the Corona and
Empire stocks and Late Cretaceous and Paleocene stocks and dikes are
probably related, and that the Salero Formation may be related to
either group or both. Comparison with a suite of similar age from the
Sierrita Mountains (Anthony, 1986) of southeastern Arizona indicates
distinct differences. The Sierrita Mountains contain world-class
porphyry copper deposits while the Santa Rita and Empire Mountains,
twenty miles to the east, have relatively meager metal production.
ix
CHAPTER 1
INTRODUCTION
Southeastern Arizona is one of the premier copper-producing
areas of the world. Within this region, however, some areas have had
conspicuously greater mineral production than others. This work is
part of a geochemical study of two mountain ranges which differ
markedly in metal production, yet are geographically close and have
similar intrusive histories. The Sierrita Mountains contain
world-class porphyry copper deposits in igneous rocks of Laramide age.
The Santa Rita and Empire Mountains, which lie only 20 - 30 miles to
the east, have igneous units similar to those in the Sierrita
Mountains, but are relatively meager in metal production, particularly
with respect to copper. The combination of geographic proximity,
petrologic similarity, and disparity in mineral production indicates
that a study of the trace element composition of these rocks might
suggest some differences between "productive" and "nonproductive"
plutonic complexes in the southwestern United States.
Scone of the Study
This study was conducted under the supervision of Dr. Spencer
R. Titley of the University of Arizona and was part of a larger project
aimed at placing constraints on the source regions of Laramide plutons
1V
2
in southeastern Arizona. This portion of the project concentrated on
the Santa Rita and Empire Mountains, while E. Y. Anthony and N. Hess
were conducting a study of similar units in the Sierrita Mountains. In
the Sierrita study, time- and stratigraphically restricted units that
were believed to be closely related were intensively sampled so that
geochemical modeling could be combined with isotopic analyses to typify
the sources and igneous processes which were responsible for their
formation.
In this study units from a mountain range adjacent to the
Sierrita Mountains were studied so that comparisons could be made. The
samples were chosen so that: 1) the maximum dimension of the geographic area of sampling in the Santa Rita and Empire complex was greater than
the distance between the Sierrita and Santa Rita Mountains; 2) the
sampled units in the Santa Rita and Empire complex included units both
older and younger than those sampled in the Sierrita Mountains; and, 3)
correlative units were included.
The author collected and prepared all samples from the Santa
Rita and Empire complex, with Dr..Titley advising as to which units
were appropriate to the aims of the larger project. With advice from
E. Y. Anthony, the author conducted the trace element analysis on all
but three of the samples, and assisted on those three.
APPENDIX 1 lists the results of the analyses. TABLE 1 lists
the units sampled in this study, their ages, approximate outcrop areas,
and correlations to rocks in the Sierrita Mountains according to Drewes
(1981). APPENDIX 2 is a more detailed listing of the samples in this
3
TABLE 1. Sampled Units with Ages and Correlations by Drewes (1981)
Unit: Salero Formation (SF: SFN and SFS)Age: Upper Cretaceous, upper CampanianOutcrop: Southern Santa Rita Mountains in the Salero Mountain
vicinity and an area centered between the extreme northern Santa Rita mountains and the Empire Mountains, extending into both ranges.
Sierrita correlative: Demetrie Volcanics and Red Boy Rhyolite
Unit: Quartz monzonite of Corona and Empire stocks (KLQ)Age: Upper Cretaceous, upper CampanianOutcrop: Corona stock outcrops at the extreme northern end of
the northern Santa Rita Mountains; Empire stock outcrops in the west-central Empire Mountains, about 6 miles southwest of the Corona stock.
Sierrita correlative: Demetrie Volcanics and Red Boy Rhyolite
Unit: Josephine Canyon Diorite (JCD)Age: Upper Cretaceous, MaestrichtianOutcrop: Southern Santa Rita MountainsSierrita correlative: Diorite and andesitic intrusive rocks dated
at 67 m.y. (diorite phase studied by Anthony, 1986)
Unit: Elephant Head Quartz .Monzonite (EHQM)Age: Upper Cretaceous, MaestrichtianOutcrop: Northwestern part of southern Santa Rita MountainsSierrita correlative: Diorite and andesitic intrusive rocks dated
at 67 m.y. (diorite phase studied by Anthony, 1986)
Unit: Latitic to dacitic plugs and dikes (TKP)Age: Upper Cretaceous, Maestrichtian to PaleoceneOutcrop: Several small plugs in the Salero Mountain area of the
southern Santa Rita Mountains (and dikes throughout the Santa Rita Mountains)
Sierrita correlative: None but interpreted as being emplaced atboundary between dioritic and andesitic intrusive rocks (67 m.a.) and Ruby Star Granodiorite (59-60 m.a.) and biotite rhyolite (57 m.a.)
Quartz latite porphyry (GV)PaleoceneNorthern Santa Rita and Empire Mountains as plugs and dikes.correlative: Quartz monzonite porphyry stocks and dikes (ore porphyry) 54-56 Ma.
Unit:Age:Outcrop:
Sierrita
4
study, with more precise sampling sites, units, ages, and correlations
to Sierrita units according to Drewes (1981). Figure 1 shows sample
locations and the relative positions of the Santa Rita-Empire and
Sierrita Mountains. Samples from various other units were also
analyzed to ensure that analyses of the units of interest could be
distinguished from obviously unrelated rocks. These control samples
include a mid-Tertiary rhyolitic dike from the Santa Rita Mountains
(TRD-GV-1), the Jurassic Harris Ranch Quartz Monzonite from the
Sierrita Mountains (HRQM-1), and a late Tertiary porphyry from the
Yandera porphyry copper deposit of Papua New Guinea (Y-l), collected by
Dr. Titley.
Pertinent information about the samples from the Sierrita
Mountains can be found in Anthony (1986). Discussion of those samples
is included in this report only for comparison. Unless explicitly
stated, any further references to "samples" or "units" in this report
will refer to samples collected by the author in the Santa Rita and
Empire Mountains.
Physiography and Geology of the Santa Rita and Empire Mountains
The Santa Rita, Empire, and Sierrita Mountains are within the
Basin and Range Province of Arizona, specifically within the Porphyry
Copper Block subprovince of Wilkins (1984) (Figure 1). The Santa Rita
Mountains are believed to be a tilted fault block formed during a
middle to late Tertiary period of extensional tectonics. To the west
is the Santa Cruz River valley, which is quite linear and narrow with a
5
SierritaMountains
10 miles
ARIZONA
Figure 1. Santa Rita and Empire and Sierrita Mountains, SE Arizona
6
north-south orientation, as is typical for this area (Wilkins, 1984).
It separates the Santa Rita Mountains from the Sierrita Mountains.
The Santa Rita Mountains are divided physiographically and
geologically by the Sawmill Canyon fault zone (Figure 2). This is a
major structural feature in the area and can be traced across the Santa
Cruz graben into the Sierrita Mountains to the west (Titley, 1982) and
across the Sonoita Basin into the Canelo Hills and Huachuca Mountains
to the east (Drewes, 1981). The Sawmill Canyon fault zone is marked by
a narrow linear zone of steeply tilted to overturned fault blocks of
Paleozoic and Triassic sedimentary rocks that are on strike (northwest)
and in line with a much wider zone of steeply tilted fault blocks of
Paleozoic and Triassic sedimentary rocks which compose the northern
part of the Canelo Hills.
The southern Santa Rita Mountains are characterized by: a
maximum elevation of approximately 9,500 feet; a NNW-trending outline
measuring about 10 miles by 15 miles; and igneous rocks ranging in age
from Triassic to Paleocene. The Sawmill Canyon fault zone is succeeded
southward by a wider belt of folded Cretaceous sedimentary rocks. There
is one small mid-Tertiary stock in this zone. Trending northwest to
north-northwest are semi-continuous outcrops in the following
succession (from northeast to southwest): 1) Lower Cretaceous volcanic
and sedimentary rocks that dip gently to the northeast (confined to the
east flank of the mountain range); 2) Upper Triassic to lower Jurassic
volcanic and partly coeval intrusive rocks that dip moderately to the
northeast; 3) Late Cretaceous intrusive rocks (64-68 my); 4) Upper
7
Figure 2. Outcrop map of the study area with sample locations
2.10 Ma have been determined (Marvin and others, 1973, Reynolds and others, 1985).
21
CHAPTER 3
ANALYTICAL METHODS
Samples were selected from outcrop based on competence and
examination by handlens. Examination of thin-sections in the
laboratory was the basis for selection of samples to be analyzed. An
additional criterion for selection of samples to be analyzed was the
competence of the sample during the first crushing stage and
examination by microscope as explained below.
A sample size of approximately 5-15 kg was preferred. After
hand crushing to one centimeter maximum dimension in the laboratory,
individual chips were examined under a microscope and discarded if
there were any visible signs of weathering and/or alteration. All vein
material was discarded. In this manner approximately 100 - 300 grams
of material was gathered for further crushing and analysis. All
samples except 20 and 21 were then powdered in a stainless steel shatter-box; samples 20 and 21 were crushed in a agate container by XRAL Ltd., Canada.
Analysis for major elements was performed by X-Ray Assay
Laboratories Limited, Don Mills, Ontario, Canada. Detection limits were 0.01%.
Analysis for minor elements was performed by Instrumental
Neutron Activation Analysis (INAA) at the laboratories of Dr. W. V.
22
23
Boynton at the University of Arizona. Irradiation of the samples was
accomplished at the TRIGA reactor at the University of Arizona: three
hours at a flux of 7 x 1 0 ^ neutrons/cm^/sec. Three standard rocks,
W-l, NBS 278, and NBS 688A were used in addition to chemical standards
for calibration and error-checking. Counting was done with an anti-Compton spectrometer for 8 hours at 5 to 10 days after irradiation
and for 4 hours at 30 to 40 days after. Error and reproducibility
figures are noted in APPENDIX 4. The reproducibility figures are
comparisons of splits from the same samples: two powder aliquots (taken
after crushing) of Sample 7, QLP-DC-1, were analyzed; Sample RS-MR-6
was re-analyzed after an earlier run; and Sample JCD-SM-1 was split
into two samples (3 and 19) before crushing.
Geochemical Evaluation of Weathering and Alteration
The main criteria for evaluation of weathering and alteration
of the samples was examination of thin-sections. In addition,
geochemical criteria were used to evaluate the degree of weathering and
alteration in the analyzed samples. Several different methods of
detecting weathering and alteration were used on these samples. Among
these are the criteria discussed by Condie and Shadel (1984), Beswick
and Soucie (1978), and Nesbitt, Marcovics and Price (1980).
The Chemical Index of Alteration (CIA) (Nesbitt and Young,
1982, Taylor and McLennan, 1985) was developed to give an indication of
chemical weathering in the upper crust. This index is based on the
fact that feldspars are the most abundant of the minerals considered
24
reactive during weathering and that calcium, sodium, and potassium are
generally more easily removed than aluminum. Thus, the proportion of
alumina to alkalies generally increases during weathering. The formula
uses molecular proportions as follows:
CIA - [Al203/(Al203+Ca0*+Na20+K20)] x 100
where CaO* is the amount of CaO incorporated in silicates (Nesbitt and
Young, 1982). Typical values for some minerals and rock types are
given with the calculated values for these samples in TABLE 2. As can
be seen, all of the samples except 6 (GV) are less than the suggested upper limit of fresh granites and granodiorites.
As shown in APPENDIX 3, significant amounts of corundum appear
in the norm of Sample 6 combined with an A/CNK ratio much higher than any other of the samples, probably indicative of weathering. The thin
section of Sample 6 also showed it to be weathered, but it was the best sample from the dikes in the Greaterville area and was included both
for that reason and to give an indication of the effects of weathering.
25
TABLE 2. Chemical Index of Alteration (C.I.A.) for Samples (Nesbitt and Young, 1982)
CIA MATERIAL
Typical Values for Minerals
50 Unaltered albite, anorthite, and potassic feldspars0 diopside75 idealized muscovite75-85 illite100 kaolinite and chlorite
Typical Values for Rocks
30-45 fresh basalts45-55 fresh granites and granodiorites55-70 loess70-75 shales
Sc ppm Ti ppm Co ppm Ni ppm Zn ppm As ppm Rb ppm Sr ppm Y ppm Zr ppm Nb ppm Sb ppm Cs ppm Ba ppm La ppm Ce ppm Nd ppm Sm ppm Eu ppm Tb ppm Yb ppm Lu ppm Hf ppm Ta ppm Th ppm U ppm
Sc ppm Ti ppm Co ppm Ni ppm Zn ppm As ppm Rb ppm Sr ppm Y ppm Zr ppm Nb ppm Sb ppm Cs ppm Ba ppm La ppm Ce ppm Nd ppm Sm ppm Eu ppm Tb ppm Yb ppm Lu ppm Hf ppm Ta ppm Th ppm U ppm
Sample numbers are given as they appear in the text and in the figures. Locations are given first as latitude and longitude (estimated from map locations), second as a cadastral description with the appropriate quadrangle name, and third as a description using local features, natural and man-made. Units are given first as the original unit name as described by Drewes (for the Sahuarita and Mt. Wrightson 7-1/2" quadrangles) or Finnell (for the Empire 15" quadrangle) during the 1970's, and second as listed by Drewes (1980, 1981) in later works on the tectonics of southeastern Arizona (in brackets). Ages are listed first according to Drewes (1980) with radiometric determinations (in brackets) by Marvin and others (1973) as recalculated by Reynolds and others (1985). Sierrita correlatives are listed according to Drewes (1981).
87
88
Field no: JCD-SM-1
SAMPLE 3
Location: 31°32,45" 110°49' SE1/4,SW1/4,SW1/4,SEC4,T22S,R15E(Patagonia 7-1/2") South Santa Rita Mts., 1/4 mile ESE of Weatherhead Ranch, at concrete bridge over Patagonia - Alto road.
Age: Upper Cretaceous (Drewes, 1980) [ 68.70 +/- 3.00 Ma, K-Ar(Marvin and others, 1973, Reynolds and others, 1985) ]
Sierrita correlative: Diorite and andesitic intrusive rocks dated at 67 Ma.
SAMPLE 4
Field no: GV-AG32-1Location: (approximate) 31°45'30" 110°46' NW1/4,SEC25,T19S,R15E
Unit:
(Helvetia 7-1/2") North Santa Rita Mts., drill core from Granite Mountain in the Greaterville district.Tql (Drewes, 1971b) - Quartz latite porphyry stocks and dikes [ Tip (Drewes, 1980) - Uppermost Cordilleran (Laramide)
Sierrita correlative: Quartz monzonite porphyry stocks and dikes (ore porphyry) 54-56 Ma (Drewes, 1981)
SAMPLE 5
Field no: GV-GMN-5Location: 31°46' 110°46'45" NW1/4,SE1/4,SE1/4,SEC23,T19S,R15E
Unit:
(Helvetia 7-1/2") North Santa Rita Mts., outcrop on south side of the Forest Service road from the Greaterville site to Melendrez Pass where the road cuts the westernmost of the main stocks in the Greaterville area.Tql (Drewes, 1971b) - Quartz latite porphyry stocks and dikes [ Tip (Drewes, 1980) - Uppermost Cordilleran (Laramide)
2.30 Ma, 57.1 +/- 2.10 Ma, 57.6 +/- 2.10 Ma, K-Ar (Marvin and others, 1973, Reynolds and others, 1985)]
Sierrita correlative: Quartz monzonite porphyry stocks and dikes (ore porphyry) 54-56 Ma
SAMPLE 6
SAMPLE 7
Field no: QLP-DC-1Location: 31°37'30" 110°52'30" SW1/4,NE1/4,NW1/4,SEC26,T17S,R16E (Mt.
Fagan 7-1/2') North Santa Rita Mts., 1 mile NNE of Pauline Mine adjacent to wash which can be reached by going south on the dirt road immediately east of the intersection of Sahuarita and Coronado Roads.
Sierrita correlative: Demetrie Volcanics and Red Boy Rhyolite
SAMPLE 11
Field no: KLQ-ES-2Location: 31°45'15" 110°39' SW1/4,SW1/4,SEC31,T17S,R17E (Mt. Fagan
Unit:
7-1/2") Empire Mts., 3/4 mile E of Arizona State Highway 83 above Davidson Canyon.Ke (Finnell, 1971) - Quartz monzonite of Empire Mountains stock [ Klq (Drewes, 1980) - Lower Cordilleran (Laramide) Igneous and Sedimentary Rocks, lower quartz monzonite and granodiorite ].
Age: Upper Cretaceous (Drewes, 1980) [ 71.90 +/- 2.50, K-Ar(Marvin and others, 1973, Reynolds and others, 1985)]
Sierrita correlative: Demetrie Volcanics and Red Boy Rhyolite
SAMPLE 12
Field no: AC-EH-1Location: 31°42' 110o55' NE1/4,NW1/4,NW1/4,SEC16,T20S,R14E (Mt.
Unit:Hopkins 7-1/2") South Santa Rita Mts., Agua Caliente Canyon. Keqc (Drewes, 1971a) - Elephant Head Quartz Monzonite, quartz monzonite of the Quantrell stock, coarse phase [ Kq (Drewes, 1980) - Main Cordilleran (Laramide)Igneous Rocks, quartz monzonite ].
Age: Upper Cretaceous (Drewes, 1980) [ 74.30 +/- 3.30, K-Ar(Marvin and others, 1973, Reynolds and others, 1985)]
Sierrita correlative: Demetrie Volcanics and Red Boy Rhyolite
SAMPLE 16
SAMPLE 17
Field no: BSM-QL-1Location: 31°38'10" 110°53' NW1/4,SE1/4,NUl/4,SEC2,T21S,R14E (Mt.
Hopkins 7-1/2") South Santa Rita Mts., 1 mile ESE of Bull Springs Mine and 3/4 mile NNE of Helvetia Mine.
Unit: Kip (Drewes, 1971a) - Quartz latite porphyry, stocks, dikes,and a sill [ Tkp (Drewes, 1980) - Main Cordilleran (Laramide) Igneous Rocks, porphyritic and aplitic intrusive rocks ].
Age: Paleocene and Upper Cretaceous (Drewes, 1980)Sierrita correlative: None but interpreted (Drewes, 1980) as being
emplaced at the boundary between diorite and intrusive andesitic rocks (67 m.a.) and Ruby Star Granodiorite (59 - 60 m.a.) and biotite rhyolite (57 m.a.)
SAMPLE 18Field no: SM-KSW-3Location: 31°37'15" 110°52,30" SE1/4,NE1/4,SECll,T21S,R U E (Patagonia
7-1/2") South Santa Rita Mts., .8 mile N of Baca Float No. 5 boundary on road between Bull Springs Mine and Alto.
coarse-grained quartz diorite [ Kd (Drewes, 1980) - Main Cordilleran (Laramide) Igneous Rocks, diorite and quartz diorite ].
Age: Upper Cretaceous (Drewes, 1980) [ 68.70 +/- 3.00 Ma, K-Ar(Marvin and others, 1973, Reynolds and others, 1985)]
Sierrita correlative: Diorite and andesitic intrusive rocks dated at Ma
SAMPLE 20
Field no: JCD-SM-5Location: 31°32'45" 110°49' SE1/4,SW1/4,SW1/4,SEC4,T22S,RISE
(Patagonia 7-1/2") South Santa Rita Mts., 1/4 mile ESE of Meatherhead Ranch, 200 yards NW of concrete bridge (sampling site for JCD-SM-1 and -IX) over Patagonia - Alto road.
Sierrita correlative: Quartz monzonite porphyry stocks and dikes (ore porphyry) 54-56 Ma
APPENDIX 3
MAJOR ELEMENT VALUES AND RATIOS, PETROLOGIC INDICES, AND BARTH KATANORMS
94
95
SAMPLE: 3 IDENTIFIER: JCD-SM-1
OXIDE WT PCT CAT.PCT FACTOR WT PCT CAT PCT
SI02 58.40 54.79 A 39.43 51.82t i o2 0.91 0.64 F 39.95 23.83AL9O1 16.50 18.25 M 20.62 24.36FE203 6.86 1.70FEO 0.0 3.14MNO 0.11 0.08 A 35.04 49.92MGO 3.54 4.95 C 29.45 27.12CAO 5.69 5.72 F 35.51 22.96NA20 3.90 7.09k 2o 2.87 3.44C02 0.0 0.0 NA 31.30 43.66p2°5 0.24 0.19 K 23.03 21.14S 0.0 0.0 CA 45.67 35.20H20 1.08TOTAL 100.10 A/CNK 0.83
PETROLOGIC INDICES FACTOR
SOLIDIFICATION INDEX (KUNO) 20.49 Q 9.16THETA (SUGIMORA) 31.28 A 21.69SIGMA (RITTMANN) 2.98 P 69.16DIFFERENTIATION INDEX 59.90 F 0.0LARSON FACTOR 6.94MODIFIED LARSON FACTOR 5.29AGPAITIC COEFFICIENT(KN/A) 0.58
BARTH NORMATIVE MINERALOGY (IN ORDER OF ABUNDANCE)
SI02 81.50 78.28 A 82.59 89.00t i o2 0.17 0.12 F 13.10 6.66AL203 9.40 10.64 M 4.32 4.35lFE203 0.88 0.64FEO 0.0 0.0MNO 0.02 0.01 A 71.71 81.08MGO 0.29 0.42 C 16.93 12.86CAO 1.31 1.35 F 11.37 6.07n a2o 2.67 4.97k 2o 2.88 3.53C02 0.0 0.0 NA 38.92 50.48P205 0.05 0.04 K 41.98 35.83s 0.0 0.0 CA 19.10 13.69h 2o 0.70TOTAL 99; 87 A/CNK 0.95
PETROLOGIC INDICES FACTOR
SOLIDIFICATION INDEX (KUNO) 4.30 Q 51.10THETA (SUGIMORA) 43.96 A 18.03SIGMA (RITTMANN) 0.80 P 30.88DIFFERENTIATION INDEX 92.51 F 0.0LARSON FACTOR 27.66MODIFIED LARSON FACTOR 13.99AGPAITIC COEFFICIENT(KN/A) 0.80
BARTH NORMATIVE MINERALOGY (IN ORDER OF ABUNDANCE)
SI02 73.60 69.59 A 82.40 87.69TI02 0.19 0.14 F 11.02 5.64AL9O3 14.30 15.94 M 6.59 6.68FE2O3 0.92 0.65FEO 0.0 0.0MNO 0.02 0.01 A 66.22 75.64MGO 0.55 0.78 C 24.93 19.50CAO 2.59 2.62 F 8.85 4.86n a2o 3.00 5.50k 2o 3.88 4.68C02 0.0 0.0 NA 31.68 42.95P2O5 0.10 0.08 K 40.97 36.55S 0.0 0.0 CA 27.35 20.49H20 0.62TOTAL 99.77 A/CNK 1.03
PETROLOGIC INDICES FACTOR
SOLIDIFICATION INDEX (KUNO) 6.57 Q 34.45THETA (SUGIMORA) 43.58 A 24.21SIGMA (RITTMANN) 1.55 P 41.34DIFFERENTIATION INDEX 84.98 F 0.0LARSON1 FACTOR 24.45MODIFIED LARSON FACTOR 12.52AGPAITIC COEFFICIENT(KN/A) 0.64
BARTH NORMATIVE MINERALOGY (IN ORDER OF ABUNDANCE)SALIC MINERALS 97.43 PERCENTQUARTZ 33.29ALBITE 27.50ORTHO 23.40ANORTH 12.45CORUND 0.78
SI02 75.80 71.39 A 89.98 93.92t i o2 0.11 0.07 F 7.60 3.73AL203 14.20 15.77 M 2.42 2.35FE20] 0.66 0.47FEO 0.0 0.0MNO 0.01 0.00 A 90.39 94.85MGO 0.21 0.29 C 1.97 1.38GAO 0.17 0.17 F 7.64 3.77NA20 3.83 6.99k 2o 3.98 4.78C02 0.0 0.0 NA 47.99 58.54P205 0.05 0.04 K 49.87 40.03S 0.0 0.0 CA 2.13 1.44h 2o 1.00TOTAL 100.02 A/CNK 1.30
PETROLOGIC INDICES FACTOR
SOLIDIFICATION INDEX (KUNO) 2.42 Q 37.44THETA (SUGIMORA) 40.69 A 25.18SIGMA (RITTMANN) 1.86 P 37.38DIFFERENTIATION INDEX 98.23 F 0.0LARSON FACTOR 28.27MODIFIED LARSON FACTOR 14.88AGPAITIC COEFFICIENT(KN/A) 0.75
BARTH NORMATIVE MINERALOGY (IN ORDER OF ABUNDANCE)
SI02 65.60 62.52 A 61.03 72.77t i o2 0.46 0.33 F 27.52 14.93a l2o3 15.30 17.19 M 11.45 12.30FE203 3.58 1.41FEO 0.0 1.16MNO 0.06 0.04 A 56.55 70.89MGO 1.49 2.12 C 17.95 14.57CAO 2.52 2.57 F 25.50 14.54n a2o 4.53 8.37k 2o 3.41 4.15C02 0.0 0.0 NA 43.31 55.47P205 0.16 0.13 K 32.60 27.47s 0.0 0.0 CA 24.09 17.05h 2o 3.16TOTAL 100.27 A/CNK 0.97PETROLOGIC INDICES FACTOR
SOLIDIFICATION INDEX (KUNO) 11.40 Q 19.49THETA (SUGIMORA) 31.38 A 22.47SIGMA (RITTMANN) 2.79 P 58.04DIFFERENTIATION INDEX 80.57 F 0.0LARSON FACTOR 18.05MODIFIED LARSON FACTOR 10.36AGPAITIC COEFFICIENT(KN/A) 0.73
BARTH NORMATIVE MINERALOGY (IN ORDER OF ABUNDANCE)
SI02 59.00 57.72 A 38.31 52.58t i o2 0.82 0.60 F 45.60 27.91ALpO^ 16.70 19.26 M 16.09 19.51f e2o3 6.32 1.71FEO 0.0 2.94MNO 0.12 0.09 A 31.55 46.45MGO 2.23 3.25 C 30.90 28.89CAO 5.20 5.45 F 37.55 24.66n a2o 3.29 6.24k 2o 2.02 2.52C02 0.0 0.0 NA 31.30 43.91p2°5 0.24 0.20 K 19.22 17.74S 0.0 0.0 CA 49.48 38.35H20 4.31TOTAL 100.25 A/CNK 0.98
PETROLOGIC INDICES FACTOR
SOLIDIFICATION INDEX (KUNO) 15.95 Q 19.07THETA (SUGIMORA) 37.62 A 14.70SIGMA (RITTMANN) 1.76 P 66.23DIFFERENTIATION INDEX 60.43 F 0.0LARSON FACTOR 8.57MODIFIED LARSON FACTOR 5.82AGPAITIC COEFFICIENT(KN/A) 0.45
BARTH NORMATIVE MINERALOGY (IN ORDER OF ABUNDANCE)
SI02 68.40 63.35 A 70.12 76.14TI02 0.47 0.33 F 12.32 6.25AL203 15.40 16.81 M 17.55 17.62FE203 1.32 0.92FEO 0.0 0.0MNO 0.04 0.03 A 55.59 66.84MGO 1.88 2.59 C 34.64 27.68CAO 4.68 4.64 F 9.77 5.48NA20 3.81 6.84k 2o 3.70 4.37C02 0.0 0.0 NA 31.26 43.15P205 0.14 0.11 K 30.35 27.57s 0.0 0.0 CA 38.39 29.29h 2o 0.31TOTAL 100.15 A/CNK 0.82
PETROLOGIC INDICES FACTOR
SOLIDIFICATION INDEX (KUNO) 17.49 Q 22.08THETA (SUGIMORA) 37.06 A 24.31SIGMA (RITTMANN) 2.22 P 53.62DIFFERENTIATION INDEX 75.92 F 0.0LARSON1 FACTOR 18.75MODIFIED LARSON FACTOR 9.26AGPAITIC COEFFICIENT(KN/A) 0.67
BARTH NORMATIVE MINERALOGY (IN ORDER OF ABUNDANCE)
SI02 73.70 70.88 A 69.76 77.11t i o2 0.25 0.18 F 22.64 13.75AL2O3 13.90 15.76 M 7.59 9.14FE2°3 1.61 1.17FEO 0.0 0.0MNO 0.05 0.04 A 44.93 53.09MGO 0.54 0.77 C 40.49 37.44CAO 4.47 4.61 F 14.58 9.47NA20 0.70 1.31k 2o 4.26 5.23C02 0.0 0.0 NA 7.42 11.72P205 0.07 0.05 K 45.17 46.93s 0.0 0.0 CA 47.40 41.35H20 0.85TOTAL 100.40 A/CNK 1.00PETROLOGIC INDICES FACTOR
SOLIDIFICATION INDEX (KUNO) 7.54 Q 42.90THETA (SUGIMORA) 54.22 A 27.03SIGMA (RITTMANN) 0.80 P 30.07DIFFERENTIATION INDEX 74.36 F 0.0LARSON FACTOR 22.37MODIFIED LARSON FACTOR 11.51AGPAITIC COEFFICIENT(KN/A) 0.41
BARTH NORMATIVE MINERALOGY (IN ORDER OF ABUNDANCE)
SI02 72.50 67.61 A 82.66 89.30t i o2 0.22 0.15 F 13.91 7.19AL203 14.20 15.61 M 3.43 3.52FE203 1.62 1.14FEO 0.0 0.0MNO . 0.03 0.02 A 80.32 88.27MGO 0.40 0.56 C 6.17 4.62CAO 0.74 0.74 F 13.51 7.11n a2o 4.31 7.79k 2o 5.32 6.33C02 0.0 0.0 NA 41.56 52.44P205 0.06 0.04 K 51.30 42.59s 0.0 0.0 CA 7.14 4.98H20 0.70TOTAL 100.10 A/CNK 1.00PETROLOGIC INDICES FACTOR
SOLIDIFICATION INDEX (KUNO) 3.42 Q 24.02THETA (SUGIMORA) 29.98 A 32.53SIGMA (RITTMANN) 3.14 P 43.45DIFFERENTIATION INDEX 94.15 F 0.0LARSON FACTOR 26.89MODIFIED LARSON FACTOR 14.96AGPAITIC COEFFICIENT(KN/A) 0.90
BARTH NORMATIVE MINERALOGY (IN ORDER OF ABUNDANCE)
SI02 61.80 59.16 A 56.86 69.30TI02 0.57 0.41 F 31.08 17.36AL203 16.60 18.74 M 12.06 13.34FE2°3 4.28 1.49FEO 0.0 1.59MNO 0.07 0.05 A 49.78 64.42MGO 1.66 2.37 C 23.01 19.44CAO 3.62 3.71 F 27.21 16.14NA20 4.32 8.02k 2o 3.51 4.29C02 0.0 0.0 NA 37.73 50.06P205 0.20 0.16 K 30.66 26.76s 0.0 0.0 CA 31.62 23.18h 2o 3.47TOTAL 100.10 A/CNK 0.95PETROLOGIC INDICES FACTOR
SOLIDIFICATION INDEX (KUNO) 11.99 Q 14.09THETA (SUGIMORA) 30.93 A 23.73SIGMA (RITTMANN) 3.26 P 62.18DIFFERENTIATION INDEX 74.26 F 0.0LARSON FACTOR 14.98MODIFIED LARSON FACTOR 8.96AGPAITIC COEFFICIENT(KN/A) 0.66BARTH NORMATIVE MINERALOGY (IN ORDER OF ABUNDANCE)
SI02 62.00 59.61 A 60.15 71.64t i o2 0.56 0.40 F 30.57 17.72AL9O1 16.70 18.93 M 9.28 10.65FE2O3 4.35 1.49FEO 0.0 1.66MNO 0.12 0.09 A 53.97 67.29MGO 1.32 1.89 C 18.60 16.07CAO 2.95 3.04 F 27.43 16.64n a2o 3.49 6.51k 2o 5.07 6.22C02 0.0 0.0 NA 30.32 41.27P2O5 0.19 0.15 .K 44.05 39.45s 0.0 0.0 CA 25.63 19.28h 2o 3.31t o t a l 100.06 A/CNK 1.01PETROLOGIC INDICES FACTOR
SOLIDIFICATION INDEX (KUNO) 9.20 Q 14.71THETA (SUGIMORA) 30.40 A 34.20SIGMA (RITTMANN) 3.86 P 51.08DIFFERENTIATION INDEX 77.65 F 0.0LARSON FACTOR 17.55MODIFIED LARSON FACTOR 10.97AGPAITIC COEFFICIENT(KN/A) 0.67
BARTH NORMATIVE MINERALOGY (IN ORDER OF ABUNDANCE)
SI02 58.90 55.34 A 40.34 52.59TI02 0.88 0.62 F 39.20 23.31AL203 16.50 18.28 M 20.47 24.11FE203 6.55 1.68FEO 0.0 2.95MNO 0.10 0.08 A 35.68 50.43MGO 3.42 4.79 C 29.65 27.22CAO 5.60 5.64 F 34.67 22.35NA20 3.80 6.92k 2o 2.94 3.52C02 0.0 0.0 NA 30.79 43.04P205 0.23 0.18 K 23.82 21.91S 0.0 0.0 CA 45.38 35.05H20 1.08to t a l 100.00 A/CNK 0.84
PETROLOGIC INDICES FACTOR
SOLIDIFICATION INDEX (KUNO) 20.35 Q 10.47THETA (SUGIMORA) 32.03 A 21.97SIGMA (RITTMANN) 2.86 P 67.56DIFFERENTIATION INDEX 60.63 F 0.0LARSON FACTOR 7.66MODIFIED LARSON FACTOR 5.56AGPAITIC COEFFICIENT(KN/A) 0.57
BARTH NORMATIVE MINERALOGY (IN ORDER OF ABUNDANCE)
SI02 57.00 53.69 A 34.89 46.58t i o2 1.08 0.77 F 42.85 26.33AL^Oq 15.50 17.21 M 22.26 27.09FE2O3 8.18 1.83FEO 0.0 3.97MNO 0.17 0.14 A 32.16 46.67MGO 4.25 5.97 C 28.34 26.95CAO 5.87 5.92 F 39.50 26.38NA20 3.61 6.59k 2o 3.05 3.67C02 0.0 0.0 NA 28.81 40.74P2O5 0.31 0.25 K 24.34 22.65S 0.0 0.0 CA 46.85 36.61H20 1.16TOTAL 100.18 A/CNK 0.78
PETROLOGIC INDICES FACTOR
SOLIDIFICATION INDEX (KUNO) 22.07 Q 7.46THETA (SUGIMORA) 28.99 A 24.69SIGMA (RITTMANN) 3.17 P 67.85DIFFERENTIATION INDEX 56.83 F 0.0LARSON FACTOR 4.57MODIFIED LARSON FACTOR 4.66AGPAITIC COEFFICIENT(KN/A) 0.60
BARTH NORMATIVE MINERALOGY (IN ORDER OF ABUNDANCE)
SI02 67.00 61.90 A 78.11 82.30t i o2 0.47 0.33 F 6.78 3.27ALfOq 15.60 16.99 M 15.11 14.43FE203 0.74 0.51FEO 0.0 0.0MNO 0.07 0.05 A 60.11 70.63MGO 1.65 2.27 C 34.67 26.56CAO 4.92 4.87 F 5.21 2.81n a2o 4.73 8.47k 2o 3.80 4.48C02 0.0 0.0 NA 35.17 47.54P2O5 0.16 0.13 K 28.25 25.13s 0.0 0.0 CA 36.58 27.33h 2o 1.16TOTAL 100.30 A/CNK 0.75
PETROLOGIC INDICES FACTOR
SOLIDIFICATION INDEX (KUNO) 15.01 Q 15.84THETA (SUGIMORA) 31.17 A 25.18SIGMA (RITTMANN) 3.03 P 58.98DIFFERENTIATION INDEX 78.85 F 0.0LARSON FACTOR 18.90MODIFIED LARSON FACTOR 9.09AGPAITIC COEFFICIENT(KN/A) 0.76
BARTH NORMATIVE MINERALOGY (IN ORDER OF ABUNDANCE)
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